Spatial pattern of HIV-1 cases of vertical transmission in Madrid (Spain): impact of demographic and socioeconomic factors

Materials and methods We performed a study of a retrospective observational cohort of 224 HIV-1 vertically infected children (≤17 years old) living in Madrid, born between 1980 and 2006. The analysis was stratified in 5 calendar periods (CP) on the basis of the changing antiretroviral treatment protocols: CP1 (80-89): children were untreated; CP2 (90-93): the standard of care was monotherapy with nucleoside analogue reverse-transcriptase inhibitor (NRTI); CP3 (94-96): children were receiving dual-NRTI therapy; CP4 (97-98): the antiretroviral regiments was HAART with a combinations of three or more drugs; CP5 (99-06): more than 60% were on HAART and less than 10% were still untreated. We assumed that vertical transmission occurred on the birth day. We georeferenciated the HIV-1 MTCT cases and we elaborated maps representing the prevalence of HIV-1 MTCT cases by the 21 districts of Madrid, with the support of ArcView Geographic Information Systems Version 3.1. Afterwards, we carried out an ecological analysis to assess the association between demographic and socio-economic characteristics of the population of the different districts of Madrid and the spatial distribution of HIV-1 MTCT cases.